Suppose a non-Muslim wants to convert to Islam but his/her partner doesn't want to convert, and they don't want to divorce because they love each other. If he/she still converts, is the marriage still valid? What should be done in such a situation in which a person has to choose between Allah and the spouse?

In many countries (which call themselves secular), inter-religious marriages are valid. So, even if one partner converts, the marriage would still be valid as per the governing law. In this situation, what should a person do if his/her spouse neither agrees to convert, nor to divorce (maybe because of love)?

2 Answers
2

In the case of the husband converting to Islam, there is nothing to the marriage, because in the original, sharee'ah it is permissible to marry a Muslim man with non-Muslim women (ah-lul kitab)

But in the case of opposite, that is for the woman to convert to Islam and her husband remaining a non-muslim, there are several things to consider:

The most correct of these opinions, in sharee'ah, is to divorce from him and enter into a (iddah) period. If her husband enters in islam during the (iddah) period she may return to him and does not need a new contract. If her husband enters in Islam after the (iddah) period, she may have to choose between returning to her husband or marrying another Muslim

O believers, when believing women come over to you as refugees, then
examine them. God alone is cognisant of their faith. If you find that
they are believers, do not send them back to unbelievers. They are not
lawful for them, nor are infidels lawful for believing women. Give the
unbelievers what they have spent on them. There is no sin if you marry
them provided you give their dowers to them. Do not retain your
(marriage) ties with unbelieving women. Ask for the return of what you
have spent (on them); and the unbelievers should ask for the return of
what they have spent. This is the judgement of God. He judges between
you. God is all-knowing and all-wise.
[Al-Mumtahina:10]

And from hadith:

The daughter of the Prophet (peace be upon him), Zainab, was married to Abu al-Aas ibn al-Rabee during the Jaahiliyyah (pre-islmaic period), and when she converted to Islam: the marriage between them was dissolved and she followed her father (peace be upon him), and when her husband (al-Aas ibn al-Rabee) became Muslim, the Prophet (peace be upon him) reinstated the marriage.

It should be noted, that in such cases should not prefer and give priority to worldly interests on the law of God and told him, God alone knows our interest.

What @MYamanT quoted covers the known and mostly used Fiqh point of view which doesn't take into account the situation for converts in non-Muslim countries. I would like to add here an Answer or an Ijtihad for converts in a Non-Muslim country from a woman's perspective (woman converted but her husband not), as this is the most difficult issue!

Situation for converts in non-muslim countries

For a converted woman who lives in a non muslim country one should take into account her situation and maybe look at some not that popular fatwas about the matter we can find that Sheikh al-Qaradawy quotes that ibn al-Qayyim al-Jawziya counted 9 different opinions here just 3 of them revealed in the article:

We can find that 'Omar ibn al Khatab (May Allah be pleased with him) as quoted by ibn al-Qayyim that he gave a former christian woman, which converted but didn't leave her non muslim husband (and homeland?) the choice between leaving her husband or staying beside him, Sheikh al-Qaradawy interprets the narration as even they will stay together as husband in wife with all meanings of the matter (including intercourse!).

An other Narration mentioned by ibn al-Qayyim from 'Ali ibn Abi Talib (May Allah be pleased with him) said that she could stay with him and wait for him to convert but she shouldn't let him make possession of her (having intercourse) this was the favorite opinion of ibn al-Qayyim and ibn Tayymiya.

A 3rd Narration quoted by ibn al-Qayyim from Imam az-Zuhari (May Allah be pleased with him) says that they could stay together until a court ( i guess he by this means: an Islamic or shari'a court) or a higher authority separates them!

These 3 Opinions are valid as in (60:10) the converted woman left their non-Muslim husbands and came to Medina (ard al-Islam) to a Muslim community/country! So if the wife one day leaves her non-Muslim husband to a Muslim country the situation will change and the former fatwas should be applied! Else if she stays with her husband the ruling of (60:10) doesn't apply as a necessary condition (leaving the non-Muslim husband or leaving the non-Muslim country -> ard al-kufr) is not fulfilled, so the ruling here should be handled differently!

A point which is stated by Abu al 'ala' al Mawdodi is: That if the Marriage itself is regarded as invalid in Islam they would be divorced automatically: For example a woman who married a mahram.

Abu al 'ala' al Mawdodi added that in any case the woman should reject having intercourse with her (non-Muslim) Husband and after the waiting period she could choose still to wait for him or to leave him. As from a shari'a point of view her marriage is still valid but considered as made temporary inactive! And he -in case she wants to separate- advises to do a legal divorce!

These statements are based on an article which reports some discussion in the European Council For Fatwa and Research.

Thank you for your interest in this question.
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